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swingdown_span bridges

I am getting ready to attempt building a swing-down span crossing on my layout. I have seen some pictures of some on other layouts and in a bench work book. My question is can anyone with experience give me any " pointers ", such as: alignment maintenance problems electrical problems and any advice . I want to build a 32" crossing using 3/4" ply cork roadbed and c83 flex using a " spring hinge " It would be 6" wide using 1" by 3" as " T " stiffeners. I would imagine the hinge post should be solidly anchored to floor?? Also the " locking connection end " be anchored" to floor. Where can I get detailed drwg or sketches???

Any help would be greatly appreciated.

Kevin

Reply to
kevin mahoney
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The open end needs to have locators for both side to side and in/out so that the rail ends match each and every time. A pair of pins can do this job nicely. You will also want the plate on which the pins are to be movable so that ou can occasionally align the two parts to the rails. Also allow one end of the railroad to be a bit flexible so that the bridge will control the position rather than the layout will.

-- Bob May Losing weight is easy! If you ever want to lose weight, eat and drink less. Works evevery time it is tried!

Reply to
Bob May

Add a micro switch at each end actuated by the span being put in place. The switches can turn off the last block each side of the open gap. (analogue or DCC)

Regards, Greg.P.

Reply to
Gregory Procter

The axis of the hinge pin must be above and usually behind the joint in the rails, so that the rails will rise up cleanly. Guard rails are necessary at each gap. Stagger the breaks in the running rails and the guard rails.

bluntly pointed pins dropping into "funneled" holes at both ends of the bridge will maintain alignment pretty well.

all of this is prototype, BTW.

Reply to
SailNrails

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